Why is the GOP having such trouble with health care? Simple. They talked themselves into opposing their own best plan for health care. You see, back when Bill and Hillary Clinton had a congressional majority and wanted to fix the whole health care thing, Republicans were worried that Democrats might socialize the entire medical industry. So the conservative Heritage Foundation released the very best plan for a market-based health care system that preserved the insurance industry. The Clinton plan failed. Fast forward 20 years. Obama has Democratic majorities in Congress, and wants to fix the health care industry. And being a centrist, he opens negotiations by proposing… the very best plan for a market-based health care system that preserved the insurance industry. Yes, the ACA is nothing other than the 1990’s Heritage Foundation plan. Literally point for point. Obama, the incrementalist, was hoping to attract bipartisan support for reform by using THE Republican plan as the starting point. It didn’t work. Every last Republican voted against it. And quite a few on the left complained that he should have just gone all the way to single payer, since he was never going to get any Republican support anyway. But Obama, for better or worse, started off trying to be bipartisan.

After the ACA became law, Republicans called it “Obamacare” and attacked it relentlessly, even though it was THE Republican health care plan from the past two decades. To emphasize: the ACA is the only logical market-based plan that can work, as every Republican policy expert from the 1990s onwards will tell you. Fast forward to 2017. Republicans have been saying for 7 years that they want to “repeal and replace” the law. And for seven years policy experts have been asking, “With what?”. Because the ACA is the Republican health care plan. And for seven years not one of the “repeal and replace” crowd has even tried to articulate what they are FOR, only that the ACA has to go. So here they are, with the presidency and both houses of congress. And they don’t have a clue what to do, because the ACA is the Republican health care plan. So now they are trapped by their own rhetoric, and their choices are:
To intentionally fail (if they can somehow blame someone else).

To tweak the ACA a tiny bit, declare victory, and then move one hoping that there isn’t too much damage.
To full on repeal it and helplessly watch the disaster while hoping the electoral cost isn’t too epic.
There are no other options. Because the ACA is the Republican health care plan. Now you see why replacing the ACA is so difficult for Republicans? Boy is that Obama sneaky! He laid all sorts of traps!

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Some people (PolitiFact) might point out that this isn’t completely true, since the ACA is not word-for-word identical with anything proposed by Republicans during the 1990s. And the Heritage Foundation proposal wasn’t an actual bill (proposal for a law) but instead a policy framework. But my point remains: if you are looking for the framework for a market-based health care system that preserved the insurance industry you pretty much end up with Obamacare. Maybe not word for word. And quite a few specifics – the policy minutia – could differ. In fact, an “enhance and improve” movement by Republicans would have been welcomed by the Obama administration, since something as complex as the ACA is bound to need some adjustments to function optimally. But Republicans were intent on denying Obama any semblance of bipartisanship, so they opted for “repeal and replace” instead. Only now they can’t.